OK, after some thought (and being slightly less grumpy than yesterday), I also include options 3 and 4:

3. We have a system that will cover both 1 and 2 (more difficult but do-able I think), and have either 1 common background with 2 different slants on it (3a), or two different backgrounds that use the same system (3b).

4. We develop BOTH ideas, possibly in different main topic boards or just different threads - i.e. 2 different systems and 2 different backgrounds.

My new revised choice is now 3b, as I like my alien caused it idea, which I don't think works for the gritty scenario (which also shouldn't really have mutants, unless it's several hundred years later).

Downsides to this:
Twice as much work, people will probably only work on one or the other.

Upsides:
Twice as much fun to be had, synergistic ideas between both systems/backgrounds etc.

I don't see why we couldn't develop an efficient pared-down core mechanic for the gritty scenario, and then have a supplement of optional variants allowing for the other stuff like beasties and crit tables and the like.

But then again I don't see why someone doesn't show up at my door and hand me a few million allowing me to retire and lead a life of leisure, so what do I know. :?

meh i dont think generic systems work to be honest, D20 has very few good ports for example. Other generic systems are too complicated (hero for example) because of the need for them to cover everything in the world.

meh i dont think generic systems work to be honest, D20 has very few good ports for example. Other generic systems are too complicated (hero for example) because of the need for them to cover everything in the world.

Doesn't need to be THAT generic. We're planning a Post Apocalyptical RPG, whether it has fantastical elements or not...

meh i dont think generic systems work to be honest, D20 has very few good ports for example. Other generic systems are too complicated (hero for example) because of the need for them to cover everything in the world.

Doesn't need to be THAT generic. We're planning a Post Apocalyptical RPG, whether it has fantastical elements or not...

Rather fitting for a PA setting to have the possibility of encountering something far outside the norm I'd think. Likely to be someone who'll want psionics in their home campaign, and if it's pre-designed to fit the system, so much the better.